Bug#16400920 INNODB TRIES TO PASS EMPTY BUFFER TO ZLIB, GETS Z_BUF_ERROR

page_zip_compress_node_ptrs(): Do not attempt to invoke deflate() with
c_stream->avail_in, because it will result in Z_BUF_ERROR (and
page_zip_compress() failure and unnecessary further splits of the node
pointer page). A node pointer record can have empty payload, provided
that all key fields are empty.

Approved by Jimmy Yang

storage/innodb_plugin/ChangeLog

+2013-02-27	The InnoDB Team
+
+	* page/page0zip.c:
+	Fix Bug#16400920 INNODB TRIES TO PASS EMPTY BUFFER TO ZLIB,
+	GETS Z_BUF_ERROR
+
 2013-01-21	The InnoDB Team
 
-	* buf/buf0buf.cc, handler/ha_innodb.cc:
+	* buf/buf0buf.c, handler/ha_innodb.cc:
 	Fix Bug#16067973 DROP TABLE IS SLOW WHEN IT DECOMPRESSES
 	COMPRESSED-ONLY PAGES
 

storage/innodb_plugin/page/page0zip.c

 /*****************************************************************************
 
-Copyright (c) 2005, 2011, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 2005, 2013, Oracle and/or its affiliates. All Rights Reserved.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -837,12 +837,13 @@ page_zip_compress_node_ptrs(
 		c_stream->next_in = (byte*) rec;
 		c_stream->avail_in = rec_offs_data_size(offsets)
 			- REC_NODE_PTR_SIZE;
-		ut_ad(c_stream->avail_in);
 
+		if (c_stream->avail_in) {
 			err = deflate(c_stream, Z_NO_FLUSH);
 			if (UNIV_UNLIKELY(err != Z_OK)) {
 				break;
 			}
+		}
 
 		ut_ad(!c_stream->avail_in);